A 10-key adding machine comes really handy and has the numbers zero through nine arranged chronologically. It has function keys for the purpose of addition, multiplication, division and subtraction. 

There’s also a total button (often shown as an equal to sign), a decimal button, a display screen, a memory key and a clear-all key within. Using this calculator is really simple overall.

In the absence of an authentic 10-key calculator, many people now use the number pad that is available on a computer or laptop keyboard. It offers much of the same basic functions and layout of the main keys – the math functions, numbers, decimal amongst others and enter in place of the equal sign.

However, the display is instead on your computer or laptop screen, rather than the keypad itself.

The way it functions is that the middle finger gets positioned on the five, the index over the four, and the ring over the three. Each works on the numbers above and below that row, too. Using the thumb and pinkie finger (little finger) on the zero and equals/functions keys help.Although it can be challenging for those with not-so-graceful outer digits, you’ll eventually develop the dexterity in your little finger and thumb. It will speed things up for you tremendously over time.